Struct MemoryDatabase 

pub struct MemoryDatabase { /* private fields */ }

Records kept in memory, on desktop and in the browser. Any number of spaces share them, and each sees what the others committed.

With Self::stored_in they are also kept in a Storage between runs: read when it opens, written after every commit. Self::export_json and Self::import_json move all of them in and out at once.

Implementations

impl MemoryDatabase

pub fn new(entities: Vec<EntityInfo>) -> Result<Self, ModelError>

A database with these entities and no records.

pub fn stored_in( self, storage: impl Storage + 'static, name: impl Into<String>, ) -> Result<Self, SpaceError>

Keeps the records in storage under name: what is there is read now, and every commit writes them all back. Records of entities the database no longer has are left out.

pub fn was_restored(&self) -> bool

Whether Self::stored_in found records kept from before, so an app can put its first records in only once.

pub fn storage_problem(&self) -> Option<String>

What went wrong the last time the records were written to their storage, if it did.

pub fn export_json(&self) -> String

Every record, as JSON: {"format": 1, "next_key": 7, "records": {"Account": [{...}]}}. Dates are {"days": .., "seconds": ..}; the rest are plain JSON values.

pub fn import_json(&self, text: &str) -> Result<usize, SpaceError>

Puts these records, as Self::export_json writes them, in place of all there are, and keeps them if the database is stored. Returns how many there are. Nothing changes if anything is wrong: an entity it does not have, a record without its key, a value that cannot be read.

pub fn space(&self) -> MemoryObjectSpace

A new unit of work over these records.

Trait Implementations

impl Clone for MemoryDatabase

fn clone(&self) -> MemoryDatabase

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for MemoryDatabase

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.